| 摘要 |
PURPOSE:To eliminate the need for a multiplier and to realize an optional transfer function by constituting a digital filter with a counter, a subtractor and a rate multiplier or the like. CONSTITUTION:A basic filter circuit 11 is constituted by the subtractor 3, the rate multiplier 5 inputting an absolute value output 3 of the subtractor 2, and an up-down counter 8 taking an output 7 of the rate multiplier 5 as clock input and a code output 4 of the subtractor 2 as its increase/decrease coefficient input. Two basic filter circuits 11 are connected in cascade and an output o(t) is inputted to input terminals Z1(t), Z2(t) of the basic filter circuits so as to form a filter having a 2nd order transfer function. |
